Heater



July 24, 1956 A. Y. DOWELL HEATER Filed Nov. 17, 1952 INVENTOR HEAT EXCHANGE United States Patent HEATER Alvis Yates Dowell, Washington, D. C., assignor to Radiator Specialty Company, Charlotte, N. C., a corporation of North Carolina Application November 17, 1952, Serial No. 320,973

4 Claims. (Cl. 257-246) The invention relates to heaters of the character employed for extracting heat ordinarily wasted in smoke and products of combustion escaping through fines and chimneys to the atmosphere.

Heretofore heaters of many kinds have been produced, however, they have been complicated, expensive, impractical and otherwise unsatisfactory failing to solve the problem of the recovery of heat being wasted.

It is an object of the invention to provide a simple, inexpensive heater for extracting heat from a flue or chimney and by means of which a substantial saving in heat can be satisfactorily and efiiciently accomplished.

Another object of the invention is to provide a heater which can be applied to a conventional flue or pipe which extends to a chimney through which the smoke is discharged, and which heater can be used for heating with or without recirculation, as well as a heater constructed to extract and save maximum heat.

Further objects and advantages, of the invention will be apparent from the following description taken in conjunction with the accompanying drawings, wherein:

Fig. 1 is an elevation disclosing one application .of the invention as applied to the smoke pipe of a furnace.

Fig. 2 is a longitudinal section through the heater of Fig. 1.

Figs. 3, 4, 5 and 6 are fragmentary perspectives of the ends of four additional kinds of heaters, and

Fig. 7 is a diagrammatic view illustrating the use of one of the heaters in supplying heat to a room or space.

Briefly stated, the invention comprises a heater which may be substituted for a joint or section of a pipe through which smoke or other products of combustion are discharged to the atmosphere. The heater comprises an inner or smoke pipe about which is concentrically disposed a structure such as fins or the like therein in order to extract maximum heat from the wall of the smoke pipe. A blower preferably is employed for forcing air to be heated through the heater in contact with the heat exchange structure so that the heated air may then be used for heating a room or the like.

With particular reference to the drawing, heat in smoke from any source such as for example a furnace 10 is discharged through a series of pipe sections or fiue 11 to a chimney 12 all of which are conventional.

Around the pipe 11 is disposed a larger pipe or jacket 13 of similar conventional character and including rivets 14. The pipe 13 may be of any desired character.

Between the pipes 11 and 13 there is disposed structure which provides extended surfaces or fins over which air can flow. This facilitates the conduction of heat from the wall of the pipe 11 into the space between the pipes 11 and 13. The heat exchange structure illustrated between the pipes 11 and 13 may be of any desired character, however, as shown in Figs. 2, 3, 4 and 5, it consists of spring members 15, 16, 17 and 18. The spring members 16, 17 and 18 have axial folds and are generally in the nature of split rings with joints 19, 20 and 21. The spring heat exchange members 16, 17 and 18 being in ice 2 difierent shapes or over all configuration depending "upon that preferred and suitable for the particular installation. This spacing structure maintains the pipes in their concentric relation.

In Fig. 2 the member 15 is spiral to cause the air to travel in a spiral path around the smoke pipe before it is discharged through the outlet 22. Y Y

In Fig. 3 the heat exchange member 16 consists of an annulus havingaxially disposed portions with flat bottoms and tops and with the connecting portions inclined relative to the diameter of the concentric pipes. The heat exchange member of Fig. 4 is similar to that of Fig. 3 except that the axially disposed portions'at the top are narrower and consequently these portions may be described as triangular since they have greater contact with the inner pipe than with the outer pipe. With this construction transfer of heat from the heat exchange member to the outer pipe will be reduced.

The spring ring heat exchange member 18 of Fig. 5 includes corrugations or convolutionswhich alternately engage the exterior surface of the smoke pipe and the interior surface of the pipe which forms the jacket.

In Fig. 6 the smoke pipe is the same, but theouter pipe or jacket 13' is formed of two semi-cylindrical sections each having a U-shaped slot 23 along one side edge and an inwardly turned tongue 24 along itsopposite edge so that when two of these sections are longitu dinally together they form a complete pipe section with diametrically disposed flanges which extend inwardly sufficiently to engage a smoke form 11 on which the jacket is assembled, thus dividing the space between the smoke pipe and the jacket into a pair of chambers, one on each side of the smoke pipe. In each of these chambers, preferably is disposed a semi-circular heat conducting member 25 substantially equal to one-half of either of the heat exchange members 16, 17 or 18 of Figs. 3, 4 and 5. With the heater of Fig. 6 the inlet and discharge will be located at the same end so that the air will traverse each chamber before being discharged.

The heaters of Figs. 1 to 7 inclusive may include end caps 26 to maintain the parts in assembled relation with the outer casings or jackets in properly spaced relation to the smoke pipes 11 on which they are mounted. If desired, air to be heated may be admitted by, omitting the upper end cap in Fig. 2.

If it is desired to reduce the flow'of heat from the heat exchange member to the outer pipe, this can be accomplished by use of a sleeve of insulation or by the spacing of the heat exchange member slightly from the outer jacket by the end caps 26.

In Fig. 7 is disclosed the heater employed for supplying heat to a room in a circulating system, air being taken through pipe 28 through the heat exchanger or heater under the influence of the blower 29 and returned to the room through the return pipe 30.

It will be obvious to those skilled in the art that various changes may be made in the invention without departing from the spirit and scope thereof and therefore the invention is not limited by that which is shown in the drawing and described in the specification but only as indicated in the appended claims.

What is claimed is:

1. An economy effecting heat exchange kit for application about a smoke pipe through which medium carrying heat is adapted to pass, a jacket for said pipe comprising two semi-cylindrical segments each having inwardly directed edges disposed lengthwise of the pipe providing a tongue and a groove whereby two segments may be connected, the inwardly disposed portions of said edges being of a length corresponding to the differences in radii between said pipe and said jacket and being in contact with the pipe thereby providing longitudinal Patented July 24, 1956 partitions between said pipe and jacket when the parts are assembled, heat exchange structure for conducting heat from said pipe into the space between said pipe and said ,jacket, said heat exchange structure being of spring material of good heat conducting properties and of a size and configuration to resiliently engage said pipe and jacket, and being formed of longitudinal segments disposable between and corresponding to the space between said longitudinal partitions, removable caps for disposition over the ends of said jacket, means for the admission and discharge of air into the space between said pipe and jacket, and means for producing movement of air through said space. 1 1

2. Economy effecting heat exchange structure comprising a pipe through which medium carrying heat is adapted to pass, a jacket for said pipe comprising multiple segments each having inwardly directed edges disposed lengthwise of thepipe providing a tongue and a groove whereby two segments may be connected, the inwardly disposed portions of said edges being of a length corresponding to the differences in radii between said pipe and said jacket and being in contact with the pipe thereby providing longitudinal partitions between said pipe and jacket when the parts are assembled, heat exchange structure for conducting heat from said pipe into the space between said pipe and said, jacket, said heat exchange structure being of spring material of good heat conducting properties and of a size and configuration to resiliently engage said pipe and jacket, and being formed of longitudinal segments disposable between and corresponding to the space between said longitudinal partitions, removable caps for disposition over the ends of said jacket, means for the admission and dischargetof air into the space between said pipe and jacket, and means for producing movement of air through said space.

3. A heater for application about a smoke pip through whichsmoke is adapted to pass comprising a jacket for said pipe composed of two semi-cylindrical segments having longitudinal edges disposed lengthwise of the pipe and providing tongue and groove connectionsbetween the segments, said edges having inwardly disposed portions of a length corresponding to the dif ferences in radii between said pipe and said jacket and being in contact with the pipe thereby providing longitudinal partitions in said heater, heat exchange structure for conducting heat from said pipe into the space between said pipe and said jacket, said heat exchange structure being of spring metal of good heat conducting properties and of a diameter and curvature to resiliently engage said pipe and being formed of longitudinal segments disposable between said pipe and said jacket and corresponding to the space about the pipe, said longitudinal segments interfitting with said partitions, end caps for disposition over the extremities of said jacket, means whereby air to be heated may be admitted into and discharged from the space between said pipe and jacket, and means for producing circulation of air through said heater.

4. A heater for application about a smoke pipe through which smoke is adapted to pass comprising a jacket for said pipe, said jacket having longitudinal edges disposed lengthwise of the pipe, said edges being connected to each other by a tongue and groove, said edges having inwardly disposed portions of a length substantially corresponding to the difierences in radii between said pipe and said jacket and being in contact with the pipe thereby providing a longitudinal partition in said heater, heat exchange structure for conducting heat from said pipe into the space between said pipe and said jacket, said heat exchange structure being of spring metal of good heat conducting properties and of a diameter and curvature to resiliently engage said pipe and being formed of longitudinal segments disposable between said pipe and said jacket and corresponding to the space about the pipe, said longitudinal segments interfitting with said partition, end caps closing the extremities of said jacket, and means whereby air to be heated may be admitted into and discharged from the space between said ,pipe and jacket.

References Cited in the file of this patent UNITED STATES PATENTS 256,955 Betts Apr. 25, 1882 1,887,760 Hauser Nov. 15, 1932 1,910,199 Brady May 23, 1933 1,930,285 Robinson Oct. 10, 1933 2,316,273 Meyer et al Apr. 13, 1943 2,378,646 Manning June 19, 1945 2,424,221 Brown, Jr. July 22, 1947 2,456,775 Fausek et al Dec. 21, 1948 2,468,909 Yeager et al. May 3, 1949 2,692,763 Holm Oct. 26, 1954 FOREIGN PATENTS 117,443 Australia of 1943 493,192 France of 1919 

